updated issue template to have a link to the codesandbox

.github/ISSUE_TEMPLATE.md

@@ -1,25 +1,28 @@
 <!--- Provide a general summary of the issue in the Title above -->
 
 ### Expected Behavior
+
 <!--- Tell us what should happen -->
 
 ### Actual Behavior
+
 <!--- Tell us what happens instead -->
 
 ### URL, screen shot, or Codepen exhibiting the issue
 
 <!--
-  -- Here's a Codepen template that serves as a nice starting point
-  -- for demonstrating an issue: http://codepen.io/pen?template=gaEGPY&editors=0010
+  -- Here's a Codesandbox template that serves as a nice starting point
+  -- for demonstrating an issue: https://codesandbox.io/s/m7mml8l0zj
   -->
 
 ### Steps to Reproduce
- 1. 
- 2. 
- 3. 
+
+1. 2. 3.
 
 ### Your Environment
+
 <!--- Include as many relevant details about the environment you experienced the bug in -->
-* Grommet version:
-* Browser Name and version:
-* Operating System and version (desktop or mobile):
+
+- Grommet version:
+- Browser Name and version:
+- Operating System and version (desktop or mobile):